The invention relates generally to a current control brush assembly and, more specifically, to a brush assembly having axial and radial filaments configured to contact a rotating shaft.
During operation of an electric motor, a static electrical charge may accumulate on the motor drive shaft due to friction between the rotating shaft and the surrounding air. In addition, friction between rotating objects electrically coupled to the shaft and the surrounding air may further increase the static electrical charge on the shaft. Moreover, in certain embodiments, the electric motor is driven by a variable frequency drive that may generate elevated common mode voltages. As a result, an electrical charge may be induced within the shaft, thereby further increasing the accumulated charge. If the shaft electrical charge exceeds a threshold value, the shaft may discharge to the motor housing, thereby increasing wear on motor elements (e.g., bearings, windings, etc.) and/or interfering with operation of objects coupled to the shaft.